As 40,000 persons contract HIV each year in the U.S., developing and disseminating effective HIV vaccines is a primary scientific and public health objective. This proposal seeks funding to conduct research on populations at risk to facilitate optimal future post-trial dissemination of HIV vaccines and maximize the vaccines' potential to help control the HIV epidemic. The specific aims are: 1) To examine consumer acceptability of HIV vaccines and intentions to change HIV risk behaviors, and how acceptability and intentions vary with attributes of the hypothetical vaccines (e.g., efficacy, side effects, cost, etc.); 2) To examine how post-trial HIV vaccine acceptability and risk behavior intentions, and their relationship to vaccine attributes, vary with sociodemographic characteristics, HIV vaccine knowledge, and barriers to and motivators for vaccine uptake; and 3) To examine the direct and indirect effects on HIV vaccine acceptability and risk behavior intentions of a broad range of independent variables derived from theory: sociodemographic characteristics, past health care experiences, past HIV risk behaviors, past HIV testing behaviors, past vaccine uptake, HIV vaccine knowledge, barriers, and motivators, using structural equation modeling. To address these aims, we will conduct a survey of a representative, probability sample of 1200 demographically diverse persons attending three types of venues in Los Angeles: Sexually Transmitted Disease Clinics, Needle Exchange Programs, and Latino Community Health and HIV Prevention Clinics. We will assess the acceptability of post-trial HIV vaccines and intentions to change risk behaviors using conjoint analysis, a technique increasingly used in health research. Hypothetical HIV vaccines with different levels of seven dichotomous attributes (efficacy, side effects, duration of protection, number of doses, route, number of subtypes, cost) are presented to elicit vaccine preferences and intentions regarding vaccine uptake and changes in risk behavior. Intentions will be compared across respondents' characteristics, e.g., whether Latinos' distrust of government mediates their lower acceptability of HIV vaccines. Results of this analysis will enable us to develop empirical, consumer-based social marketing and public health education strategies tailored to target populations, and will help guide public health agencies toward optimal dissemination of future HIV vaccines. [unreadable] [unreadable] [unreadable]